The new plastic five pound notes have been selling for as much as £200 online but could your loose change be worth a small fortune too?

Keen-eyed sellers have been flogging the new fivers to collectors wanting to get their hands on notes with specific serial numbers printed on the back beside Winston Churchill.

It's the first production run of the new notes that has collectors excited - those printed with AA, AB, and AC.

But if you’ve not come across one yet, you could still be a winner. Time to dig through your penny jar, or sift through the dusty coins on your dashboard

A variety of common coins in circulation for years have sky-high price tags, and you could literally be sitting on a tidy little sum.

Pull out your pockets, up-turn your purse or empty your wallet. Tip your coins from head to tail, as this could be a very a good day for you.

Kew Gardens 50p piece

A special edition 50p piece with Kew Gardens on the back is currently changing hands for more than £50.

Collectors have been clamouring for this rare piece of coinage, produced in 2011 to mark the 250 anniversary of the Royal Botanical Gardens.

Only 210,000 coins were produced by The Royal Mint, compared with the 22.7million featuring the Royal Arms in 2008 and 7.5million with a Girl Guiding design in 2010.

Dateless 20p piece - £100

This dateless 20p piece could be sold on for £100

A production error on the part of The Royal Mint made an inadvertent hero out of a 2008 run of 20p coins.

The mint decided to switch the date from the reverse of the coin, to the front, however an production error meant the new and old designs were mismatched – leaving a date on neither side.

Somewhere between 50,000 and 200,000 coins being put into circulation before the mistake was spotted, and a mint-condition coin now sells for up to £100.

London Olympic 50p coin - £3,000

A lasting legacy of the London Olympic games was a series of 50p coins with one of 29 designs on the back.

Some of the designs were produced in higher numbers than the rest, and a full set would normally go for £35.

Some of the rarer designers featuring football, wheelchair rugby, wrestling and tennis, can be exchanged for £3 or £4 individually.

However, the prize find, recently listed for £3,000 on eBay , is one of 600 original aquatic coins, showing water passing over a swimmer’s face, before the design was altered to show a visible face of the sportsman.

The EC commemorative 50p coin - £20

This EC commemorative 50p coin is worth up to £20

One for those Brexiteers, or not. In 1992 and 1993 the Mint issued a commemorative coin to celebrate the British presidency of the council of Europe. Just 109,000 coins were issued, compared to the usual 5-12million, making it highly collectable.

The coins are no longer in circulation because the 50p piece was reduced in size in 1997, but if you have one in your penny jar at home it could be worth as much as £20.

The 1983 ‘New Pence’ 2p coin - £650

Spotted one of these? A 'New Pence' 2p coin fetches up to £650

After British currency went decimal in 1971, all 2p coins had ‘New Pence’ on the reverse until 1981.

The Royal Mint decided to replace ‘New Pence” with ‘Two Pence’ in 1982. However, in 1983 the Mint accidentally produced a small number that bore the old inscription ‘New Pence’. These went into special collectors’ sets, but if you do find one that made its way into circulation it could be worth up to £650.

Guy Fawkes £2 coin - £16

This rare £2 coin was printed with “Pemember, Pemember" rather than "Remember, Remember" from the famous rhyme.

The Royal Mint regularly releases £2 coins with different designs and inscriptions on the edging. This mean, however, that mistakes sometimes creep in.

The Guy Fawkes coin was released in 2005 to commemorate the 400th anniversary of the gun powder plot to blow up the Houses of Parliament. On some of the coins released into circulation the inscription read “Pemember, Pemember the Fifth of November instead of “Remember, Remember”.

Those coins usually sell for around £16 on eBay.

Charles Dickens £2 coin - £8

In 2012 the Mint released a £2 coin to commemorate the 200th anniversary of the birth of Charles Dickens. The detailed reverse profile feature the names of the author’s books. Only 20,000 coins were minted, making it a collectable coin worth up to four times its face value.

Mary Rose and King James Bible £2 coins - £6

This rare coin marking the 500th anniversary of the Mary Rose - Henry VIII's mighty warship, which sunk in the Solent in 1545

Both designs were released by the Royal Mint in 2011 in limited editions of 20,000 each to mark the 500th anniversary of the Mary Rose and the 400th anniversary of the King James Bible. Both coins are already becoming collectable due to the small numbers and reach double to triple their face value.